Aircraft with multi spar box connection to fuselage

ABSTRACT

An aircraft has a vertical stabilizer with a multi-spar box and a base rib assembly secured to the multi-spar box. The base rib assembly has front longitudinal lugs, rear longitudinal lugs, and opposing middle longitudinal lugs. Front clevises corresponding to the front longitudinal lugs are secured to frame members of the fuselage of the aircraft and each has a first, second, and third mounting arms. Rear clevises corresponding to the rear longitudinal lugs are secured to frame members and each has a first, second, and third mounting arms. Middle clevises corresponding to the middle longitudinal lugs are secured to frame members and each has only first and second mounting arms. Retaining members inserted through mounting holes in each longitudinal lug and mounting holes in each corresponding clevis secures the vertical stabilizer to the fuselage.

FIELD

This disclosure relates generally to aircraft and, more specifically, toconnections between vertical stabilizers and fuselage of aircraft.

BACKGROUND

There are currently multiple configurations utilized to connect verticalstabilizers to the fuselage of aircraft. In one configuration, a groupof fittings are positioned between the vertical stabilizer and thefuselage, a first group of fasteners is used to attach the verticalstabilizer to the fittings, and a second group of fasteners is used toattach the fuselage to the fittings. However, this type of configurationis difficult to install due to the work required in confined spaces andmakes in service inspection difficult. In another configuration, lugsand standard dual wall clevises are used between the vertical stabilizerand the fuselage and oriented in a longitudinal direction and additionallugs and standard dual wall clevises are oriented in a lateral directionand positioned between each of the longitudinal lugs and clevises.However, this type of configuration is difficult to install due to therequired attachment of the lateral lugs between mid spars. In yetanother configuration, lugs and standard dual wall clevises are usedbetween the vertical stabilizer and the fuselage, but are only orientedlaterally and only positioned along the front and rear spar of thevertical stabilizer.

SUMMARY

In one embodiment of the present disclosure, an example aircraftcomprises an aircraft fuselage and a vertical stabilizer. The aircraftfuselage has a plurality of frame members and an outer skin and thevertical stabilizer has a multi-spar box. The multi-spar box includes afront spar, a rear spar, at least one mid spar positioned between andspaced apart from the front and rear spars, a first side skin extendingbetween the front and rear spar, and a second side skin, opposite thefirst side skin, extending between the front and rear spar. The frontand rear spars and the first and second side skins define an interior ofthe multi-spar box. A base rib assembly is positioned in an interior ofand secured to the multi-spar box. The base rib assembly has a pair ofopposing front longitudinal lugs, a pair of opposing rear longitudinallugs, and at least one pair of opposing middle longitudinal lugsdisposed between the front longitudinal lugs and the rear longitudinallugs. A pair of front clevises corresponding to the pair of frontlongitudinal lugs extend through corresponding apertures in the outerskin and are secured to one of the plurality of frame members. Eachfront clevis has a first mounting arm, a second mounting arm, and athird mounting arm. A pair of rear clevises corresponding to the pair ofrear longitudinal lugs extend through corresponding apertures in theouter skin and are secured to one of the plurality of frame members.Each rear clevis has a first mounting arm, a second mounting arm, and athird mounting arm. A pair of middle clevises corresponding to the pairof middle longitudinal lugs extend through corresponding apertures inthe outer skin and are secured to one of the plurality of frame members.Each middle clevis has only a first mounting arm and a second mountingarm. A plurality of retaining members are inserted through mountingholes in each front, middle, and rear longitudinal lugs and throughmounting holes in each corresponding front, middle, and rear clevises tosecure the vertical stabilizer to the aircraft fuselage.

In one embodiment, in the example aircraft of the previous embodiment,the base rib assembly comprises at least one front lateral lugpositioned between the pair of front longitudinal lugs and at least onerear lateral lug positioned between the pair of rear longitudinal lugs.

In one embodiment, in the example aircraft of any of the previousembodiments, the base rib assembly does not have any lateral lugsbetween the at least one pair of middle lugs.

In one embodiment, in the example aircraft of any of the previousembodiments, a front lateral clevis is positioned between the pair offront clevises, extends through an aperture in the outer skin, and issecured to one of the plurality of frame members. A rear lateral clevisis positioned between the pair of rear clevises, extends through anaperture in the outer skin, and is secured to one of the plurality offrame members. A front link interconnects the front lateral clevis andthe at least one front lateral lug and a rear link interconnects therear lateral clevis and the at least one rear lateral lug.

In one embodiment, in the example aircraft of any of the previousembodiments, a second front link interconnects the front lateral clevisand another front lateral lug and a second rear link interconnects therear lateral clevis and another rear lateral lug.

In one embodiment, in the example aircraft of any of the previousembodiments, a front link interconnects the at least one front laterallug and a lateral wall of one of the pair of front clevises and a rearlink interconnects the at least one rear lateral lug and a lateral wallof one of the pair of rear clevises.

In one embodiment, in the example aircraft of any of the previousembodiments, a second front link interconnects another front lateral lugand a lateral wall of the other one of the pair of front clevises and asecond rear link interconnects another rear lateral lug and a lateralwall of the other one of the pair of rear clevises.

In one embodiment, in the example aircraft of any of the previousembodiments, a front plate that has a lateral lug adjacent to andaligned with the at least one front lateral lug of the base rib assemblyis positioned adjacent an exterior surface of the front spar and issecured to the front spar and the base rib assembly. A rear plate thathas at least one lateral lug adjacent to and aligned with the at leastone rear lateral lug of the base rib assembly is positioned adjacent anexterior surface of the rear spar, opposite the front plate, and issecured to the rear spar and the base rib assembly, the rear plate. Afirst side plate that has at least one longitudinal lug adjacent to andaligned with one of the middle longitudinal lugs of the base ribassembly is positioned adjacent an exterior surface of the first sideskin and is secured to the first side skin and the base rib assembly,the first side plate. A second side plate that has at least onelongitudinal lug adjacent to and aligned with another of the middlelongitudinal lugs of the base rib assembly is positioned adjacent anexterior surface of the second side skin and is secured to the secondside skin and the base rib assembly.

In one embodiment, in the example aircraft of any of the previousembodiments, the at least one longitudinal lug of the first side plateand the corresponding middle longitudinal lug of the base rib assemblyare positioned between the first mounting arm and the second mountingarm of the corresponding middle clevis and the at least one longitudinallug of the second side plate and the corresponding middle longitudinallug of the base rib assembly are positioned between the first mountingarm and the second mounting arm of the corresponding middle clevis.

In one embodiment, in the example aircraft of any of the previousembodiments, a third side plate that has at least one longitudinal lugaligned with one of the front longitudinal lugs of the base rib assemblyis positioned adjacent an exterior surface of the first side skin and issecured to the first side skin and the base rib assembly. A fourth sideplate that has at least one longitudinal lug aligned with another of thefront longitudinal lugs of the base rib assembly adjacent an exteriorsurface of the second side skin and is secured to the second side skinand the base rib assembly.

In one embodiment, in the example aircraft of any of the previousembodiments, the at least one longitudinal lug of the third side plateis positioned between the first mounting arm and the second mounting armof a first front clevis of the pair of front clevises and acorresponding front longitudinal lug of the base rib assembly ispositioned between the second mounting arm and the third mounting arm ofthe first front clevis and the at least one longitudinal lug of thefourth side plate is positioned between the first mounting arm and thesecond mounting arm of a second front clevis of the pair of frontclevises and a corresponding front longitudinal lug of the base ribassembly is positioned between the second mounting arm and the thirdmounting arm of the second front clevis.

In one embodiment, in the example aircraft of any of the previousembodiments, a fifth side plate that has at least one longitudinal lugaligned with one of the rear longitudinal lugs of the base rib assemblyis positioned adjacent an exterior surface of the first side skin and issecured to the first side skin and the base rib assembly. A sixth sideplate that has at least one longitudinal lug aligned with another of therear longitudinal lugs of the base rib assembly is positioned adjacentan exterior surface of the second side skin and is secured to the secondside skin and the base rib assembly.

In one embodiment, in the example aircraft of any of the previousembodiments, the at least one longitudinal lug of the fifth side plateis positioned between the first mounting arm and the second mounting armof a first rear clevis of the pair of rear clevises and a correspondingrear longitudinal lug of the base rib assembly is positioned between thesecond mounting arm and the third mounting arm of the first rear clevisand the at least one longitudinal lug of the sixth side plate ispositioned between the first mounting arm and the second mounting arm ofa second rear clevis of the pair of rear clevises and a correspondingrear longitudinal lug of the base rib assembly is positioned between thesecond mounting arm and the third mounting arm of the second rearclevis.

In another embodiment of the present disclosure, an example method ofattaching a vertical stabilizer having a multi-spar box to an aircraftfuselage comprises the steps of: assembling a base rib assembly having apair of opposing front longitudinal lugs, a pair of opposing rearlongitudinal lugs, at least one pair of opposing middle longitudinallugs disposed between the front longitudinal lugs and the rearlongitudinal lugs, and a plurality of lateral lugs, each longitudinallug and each lateral lug having a corresponding mounting hole; insertingthe base rib assembly into an interior of the multi-spar box of thevertical stabilizer, the interior of the multi-spar box defined by afront spar, a rear spar, and opposing side skins; positioning a frontplate adjacent an exterior surface of the front spar and securing thefront plate to the front spar and the base rib assembly, the front platehaving at least one lateral lug corresponding to one of the plurality oflateral lugs of the base rib assembly, the at least one lateral lug ofthe front plate having a mounting hole that aligns with the mountinghole in the corresponding lateral lug of the base rib assembly;positioning a rear plate adjacent an exterior surface of the rear spar,opposite the front plate, and securing the rear plate to the rear sparand the base rib assembly, the rear plate having at least one laterallug corresponding to one of the plurality of lateral lugs of the baserib assembly, the at least one lateral lug of the rear plate having amounting hole that aligns with the mounting hole in the correspondinglateral lug of the base rib assembly; positioning a first side plateadjacent an exterior surface of a first side skin of the multi-spar boxand securing the first side plate to the first side skin and the baserib assembly, the first side plate having at least one longitudinal lugcorresponding to one of the longitudinal lugs of the base rib assembly,each of the at least one longitudinal lug of the first side plate havinga mounting hole that aligns with the mounting hole in the correspondinglongitudinal lug of the base rib assembly; positioning a second sideplate adjacent an exterior surface of a second side skin of themulti-spar box and securing the second side plate to the second sideskin and the base rib assembly, the second side plate having at leastone longitudinal lug corresponding to one of the longitudinal lugs ofthe base rib assembly, each of the at least one longitudinal lug of thesecond side plate having a mounting hole that aligns with the mountinghole in the corresponding longitudinal lug of the base rib assembly;inserting a plurality of clevises through corresponding apertures in askin of the aircraft fuselage and securing each of the plurality ofclevises to a frame member of the aircraft fuselage, wherein theclevises corresponding to the front longitudinal lugs and the rearlongitudinal lugs each have a first, second, and third mounting arms,each mounting arm having a mounting hole, and the clevises correspondingto the middle longitudinal lugs each have first and second mountingarms, each mounting arm having a mounting hole; positioning the verticalstabilizer adjacent the aircraft fuselage and aligning each longitudinallug with a corresponding clevis; and inserting a retaining memberthrough the mounting hole of each corresponding longitudinal lug andclevis to secure the vertical stabilizer to the aircraft fuselage.

In one embodiment, in the example method of the previous embodiment, themethod comprises the steps of attaching each lateral lug to a first endof a corresponding lateral link and attaching a second end of eachlateral link to a lateral clevis.

In one embodiment, in the example aircraft of any of the previousembodiments, each lateral clevis is part of a corresponding clevis.

In one embodiment, in the example aircraft of any of the previousembodiments, each lateral clevis is positioned between two clevises,extends through a corresponding aperture in the skin of the aircraftfuselage, and is secured to a frame member of the aircraft fuselage.

In one embodiment, in the example aircraft of any of the previousembodiments, assembling the base rib assembly comprises: attaching atleast one first side chord to a base rib, the at least one first sidechord including at least one of the plurality of longitudinal lugs;attaching at least one second side chord to the base rib, opposite theat least one first side chord, the at least one second side chordincluding at least one of the plurality of longitudinal lugs; attachinga front terminal fitting to the base rib, the front terminal fittingincluding at least one of the plurality of longitudinal lugs and atleast one of the plurality of lateral lugs; and attaching a rearterminal fitting to the base rib, opposite the front terminal fitting,the rear terminal fitting including at least one of the plurality oflongitudinal lugs and at least one of the plurality of lateral lugs.

In one embodiment, in the example aircraft of any of the previousembodiments, the method comprises the step of attaching at least onegenerally L-shaped shear clip between the base rib assembly and a midspar of the multi-spar box.

In one embodiment, in the example aircraft of any of the previousembodiments, the plurality of lateral lugs are located at a front of thebase rib assembly and a rear of the base rib assembly and no laterallugs are located between the front and the rear of the base ribassembly.

The features, functions, and advantages that have been discussed can beachieved independently in various embodiments or may be combined in yetother embodiments further details of which can be seen with reference tothe following description and drawings.

BRIEF SUMMARY OF THE DRAWINGS

FIG. 1 is a side view of an example aircraft;

FIG. 2 is a partial perspective view of an example multi-spar box of thevertical stabilizer of the aircraft of FIG. 1;

FIG. 3 is a partial perspective view of the multi-spar box of FIG. 2with a side skin removed;

FIG. 4 is a front perspective view of a first example base rib assembly;

FIG. 5 is a rear perspective view of the base rib assembly of FIG. 4;

FIG. 6 is a front perspective view of the base rib assembly of FIG. 4positioned within the multi-spar box of FIG. 2 with a side skin removed;

FIG. 7 is a front perspective view of the base rib assembly of FIG. 4fully assembled with the multi-spar box of FIG. 2;

FIG. 8 is a partial illustration of a portion of the fuselage of theaircraft of FIG. 1 with a first set of exemplary clevises;

FIG. 9 is rear perspective view of the multi-spar box and base ribassembly of FIG. 7 connected to the fuselage of FIG. 8;

FIG. 10 is a front perspective view of the multi-spar box, base ribassembly, and fuselage of FIG. 9;

FIG. 11 is a front perspective view of a second example base ribassembly;

FIG. 12 is a rear perspective view of the base rib assembly of FIG. 11;

FIG. 13 is a front perspective view of the base rib assembly of FIG. 11positioned within the multi-spar box of FIG. 2 with a side skin removed;

FIG. 14 is a front perspective view of the base rib assembly of FIG. 11fully assembled with the multi-spar box of FIG. 2;

FIG. 15 is a partial illustration of a portion of the fuselage of theaircraft of FIG. 1 with a second set of exemplary clevises;

FIG. 16 is rear perspective view of the multi-spar box and base ribassembly of FIG. 14 connected to the fuselage of FIG. 15;

FIG. 17 is a front perspective view of the multi-spar box, base ribassembly, and fuselage of FIG. 16;

FIG. 18 is a front perspective view of a third example base ribassembly;

FIG. 19 is a rear perspective view of the base rib assembly of FIG. 18;

FIG. 20 is a front perspective view of the base rib assembly of FIG. 18positioned within the multi-spar box of FIG. 2 with a side skin removed;

FIG. 21 is a front perspective view of the base rib assembly of FIG. 18fully assembled with the multi-spar box of FIG. 2;

FIG. 22 is a partial illustration of a portion of the fuselage of theaircraft of FIG. 1 with a third set of exemplary clevises;

FIG. 23 is rear perspective view of the multi-spar box and base ribassembly of FIG. 21 connected to the fuselage of FIG. 22; and

FIG. 24 is a front perspective view of the multi-spar box, base ribassembly, and fuselage of FIG. 23.

DESCRIPTION

Referring to FIGS. 1-3, an example aircraft 10 is illustrated having anaircraft fuselage 15 with a plurality of frame members 20 and an outerskin 25 (see FIGS. 8-10, 15-17, and 22-24) and vertical stabilizer 35with a multi-spar box 40 connected to aircraft fuselage 15. As can beseen in FIGS. 2-3, multi-spar box 40 of vertical stabilizer 35 has afront spar 45, a rear spar 50, and at least one mid spar 55 positionedbetween and spaced apart from front spar 45 and rear spar 50. In theexample shown, multi-spar box 40 has two mid spars 55, but can have anynumber of mid spars 55 appropriate for a given application. A first sideskin 60A and a second side skin 60B, opposite first side skin 60A,extend between front spar 45 and rear spar 50. Front spar 45, rear spar50, first side skin 60A, and second side skin 60B together define aninterior 65 of multi-spar box 40.

Referring to FIGS. 4-10, a first example connection between aircraftfuselage 15 and multi-spar box 40 of vertical stabilizer 35 is shown. Asbest seen in FIGS. 4-5, a base rib assembly 100 has a base rib 105 and afront terminal fitting 110, rear terminal fitting 115 opposite frontterminal fitting 110, first side chord 120, and second side chord 125opposite first side chord 120, attached to base rib 105. Front terminalfitting 110 includes a pair of opposing front longitudinal lugs 130extending parallel to a longitudinal axis A of base rib assembly 100 anda pair of front lateral lugs 135 extending perpendicular to longitudinalaxis A and positioned between the pair of front longitudinal lugs 130.As shown, front terminal fitting 110 includes two pieces, each havingone front longitudinal lug 130 and one front lateral lug 135, but couldalso be one single, unitary piece having both front longitudinal lugs130 and front lateral lugs 135, as shown in FIGS. 11-12. Rear terminalfitting 115 includes a pair of opposing rear longitudinal lugs 140extending parallel to longitudinal axis A and a pair of rear laterallugs 145 extending perpendicular to longitudinal axis A and positionedbetween the pair of rear longitudinal lugs 140. As shown, rear terminalfitting 115 is a single unitary piece having both rear longitudinal lugs140 and both rear lateral lugs 145, but could also be two pieces, eachhaving one rear longitudinal lug 140 and one rear lateral lug 145. Firstside chord 120 has at least one first middle longitudinal lug 150extending parallel to longitudinal axis A and second side chord 125 hasat least one second middle longitudinal lug 155, opposite firstlongitudinal lug 150. As shown, first side chord 120 has two firstmiddle longitudinal lugs 150 and second side chord 125 has two secondlongitudinal lugs 155, however, first and second side chords 120, 125can have any number of longitudinal lugs desired for a particularapplication. In addition, in the particular example shown, there are nolateral lugs positioned between first middle longitudinal lugs 150 andsecond longitudinal lugs 155. Therefore, in the example shown in FIGS.4-10, base rib assembly 100 has a pair of opposing front longitudinallugs 130, a pair of opposing rear longitudinal lugs 140, at least onepair of opposing middle longitudinal lugs 150, 155 disposed betweenfront longitudinal lugs 130 and rear longitudinal lugs 140, a pair offront lateral lugs 135 disposed between front longitudinal lugs 130, anda pair of rear lateral lugs 145 disposed between rear longitudinal lugs140.

As seen in FIGS. 6-7, base rib assembly 100 is positioned in interior 65of multi-spar box 40 and secured to multi-spar box 40. For example,front terminal fitting 110 of base rib assembly 100 can be secured tofront spar 45 of multi-spar box 40 with screws, bolts, welding, or anyother well-known securement method. Similarly, rear terminal fitting 115can be secured to rear spar 50 with screws, bolts, welding, or any otherwell-known securement method. In addition, mid spars 55 can be securedto base rib assembly 100 by attaching L-shaped shear clips 160 betweenbase rib 105 and/or first and second side chords 120, 125 of base ribassembly 100 and mid spars 55 with screws, bolts, welding, or any otherwell-known securement method.

Referring to FIG. 7, with base rib assembly 100 positioned in multi-sparbox 40, a front plate 165 is positioned adjacent exterior surface 47, oradjacent an interior surface, of front spar 45 and is secured to frontspar 45 and base rib assembly 100, for example, by screws that arethreaded through front plate 165, front spar 45, and front terminalfitting 110 of base rib assembly 100. Alternatively, front plate 165 canbe secured to front spar 45 and base rib assembly 100 by bolts, welding,or any other well-known securement method. Front plate 165 includeslateral lugs 170 that correspond to each of the front lateral lugs 135of front terminal fitting 110 and that are adjacent to and aligned withcorresponding front lateral lugs 135. As shown, front plate 165 is asingle, unitary piece including both lateral lugs 170, but could also betwo or more pieces, each having a single lateral lug 170 thatcorresponds to a front lateral lug 135. Similarly, a rear plate 175 ispositioned adjacent exterior surface 52, or adjacent an interiorsurface, of rear spar 50, opposite front plate 165, and is secured torear spar 50 and base rib assembly 100, for example, by screws that arethreaded through rear plate 175, rear spar 50, and rear terminal fitting115 of base rib assembly 100. Alternatively, rear plate 175 can besecured to rear spar 50 and base rib assembly 100 by bolts, welding, orany other well-known securement method. Rear plate 175 includes laterallugs 180 that correspond to each of the rear lateral lugs 145 of rearterminal fitting 115 and that are adjacent to and aligned withcorresponding rear lateral lugs 145. As shown, rear plate 175 is asingle, unitary piece including both lateral lugs 180, but could also betwo or more pieces, each having a single lateral lug 180 thatcorresponds to a rear lateral lug 145.

First side plates 185 are positioned adjacent exterior surface 62A offirst side skin 60A and are secured to first side skin 60A and base ribassembly 100, for example, by screws that are threaded through firstside plates 185, first side skin 60A, and first side chord 120.Alternatively, first side plates 185 could be secured to first side skin60A and base rib assembly 100 by bolts, welding, or any other well-knownsecurement method. Each first side plate 185 includes a longitudinal lug190 that is adjacent to and aligned with a corresponding first middlelongitudinal lug 150. In the example shown, there are two first sideplates 185 since there are two first middle longitudinal lugs 150.However, there could be any number of first side plates 185 as requiredfor the number of first middle longitudinal lugs 150. In addition,rather than individual first side plates 185, a single, unitary piecefirst side plate could be used that has multiple longitudinal lugs thateach correspond to a first middle longitudinal lug. Corresponding secondside plates (not shown) are also positioned adjacent exterior surface62B of second side skin 60B, opposite corresponding first side plates185, and are secured to second side skin 60B and base rib assembly 100,for example, by screws that are threaded through the second side plates,second side skin 60B, and second side chord 125. Alternatively, secondside plates can be secured to second side skin 60B and base rib assembly100 by bolts, welding, or any other well-known securement method. Eachsecond side plate includes a longitudinal lug that is adjacent to andaligned with a corresponding second middle longitudinal lug 155. As withfirst side plates 185, there could be any number of second side platesas required for the number of second middle longitudinal lugs 155 or,rather than individual second side plates, a single, unitary piecesecond side plate could be used that has multiple longitudinal lugs thateach correspond to a second middle longitudinal lug 155.

Third side plate 195 is positioned adjacent exterior surface 62A offirst side skin 60A and is secured to first side skin 60A and base ribassembly 100, for example, by screws that are threaded through thirdside plate 195, first side skin 60A, and front terminal fitting 110.Alternatively, third side plates 195 can be secured to first side skin60A and base rib assembly 100 by bolts, welding, or any other well-knownsecurement method. Third side plate 195 includes a longitudinal lug 200that is adjacent to and aligned with a corresponding front longitudinallug 130. Corresponding fourth side plate (not shown) is also positionedadjacent exterior surface 62B of second side skin 60B, oppositecorresponding third side plate 195, and is secured to second side skin60B and base rib assembly 100, for example, by screws that are threadedthrough the fourth side plate, second side skin 60B, and front terminalfitting 110. Alternatively, fourth side plates can be secured to secondside skin 60B and base rib assembly 100 by bolts, welding, or any otherwell-known securement method. Fourth side plate includes a longitudinallug that is adjacent to and aligned with a corresponding frontlongitudinal lug 130.

Fifth side plate 205 is positioned adjacent exterior surface 62A offirst side skin 60A and is secured to first side skin 60A and base ribassembly 100, for example, by screws that are threaded through fifthside plate 205, first side skin 60A, and rear terminal fitting 115.Alternatively, fifth side plates 205 can be secured to first side skin60A and base rib assembly 100 by bolts, welding, or any other well-knownsecurement method. Fifth side plate 205 includes a longitudinal lug 210that is adjacent to and aligned with a corresponding rear longitudinallug 140. Corresponding sixth side plate (not shown) is also positionedadjacent exterior surface 62B of second side skin 60B, oppositecorresponding fifth side plates 205, and is secured to second side skin60B and base rib assembly 100, for example, by screws that are threadedthrough the sixth side plate, second side skin 60B, and rear terminalfitting 115. Alternatively, sixth side plates can be secured to secondside skin 60B and base rib assembly 100 by bolts, welding, or any otherwell-known securement method. Sixth side plate includes a longitudinallug that is adjacent to and aligned with a corresponding rearlongitudinal lug 140.

Referring to FIG. 8, a pair of front clevises 220 correspond to the pairof front longitudinal lugs 130 and each front clevis 220 extends througha corresponding aperture 30 in outer skin 25 and is secured to a framemember 20 of aircraft fuselage 15. In the example shown, front clevises220 each have first, second, and third mounting arms 225, 230, 235 and alateral wall 240 that extends inward, generally perpendicular to thirdmounting arm 235. Similarly, a pair of rear clevises 245 correspond tothe pair of rear longitudinal lugs 140 and each rear clevis 245 extendsthrough a corresponding aperture 30 in outer skin 25 and is secured to aframe member 20 of aircraft fuselage. In the example shown, rear devises245 each have first, second, and third mounting arms 250, 255, 260 and alateral wall 240 that extends inward, generally perpendicular to thirdmounting arm 260. Pairs of middle clevises 270 correspond to the pairsof middle longitudinal lugs 150, 155 and each middle clevis 270 extendsthrough a corresponding aperture 30 in outer skin 25 and is secured to aframe member 20 of aircraft fuselage 15. Middle clevises 270 each haveonly first and second mounting arms 275, 280.

Referring to FIGS. 9-10, longitudinal lugs 190 of first side plates 185and corresponding first middle longitudinal lugs 150 of base ribassembly 100 are positioned between first mounting arm 275 and secondmounting arm 280 of the corresponding middle clevis 270 and longitudinallugs of second side plates (now shown) and corresponding second middlelongitudinal lugs 155 of base rib assembly 100 are positioned betweenfirst mounting arm 275 and second mounting arm 280 of the correspondingmiddle clevis 270. Retaining members 70, such as bolts, pins, etc., areinserted through mounting holes 152, 157 in each middle longitudinal lug150, 155, mounting holes 192 in first side plate 185 and second sideplate, and mounting holes 282 in each mounting arm 275, 280 of eachcorresponding middle clevis 270 to secure vertical stabilizer 35 toaircraft fuselage 15.

In addition, longitudinal lug 200 of third side plate 195 is positionedbetween first mounting arm 225 and second mounting arm 230 of thecorresponding front clevis 220 and the corresponding front longitudinallug 130 of base rib assembly 100 is positioned between second mountingarm 230 and third mounting arm 235 of the corresponding front clevis220. The longitudinal lug of the fourth side plate is similarlypositioned between first mounting arm 225 and second mounting arm 230 ofthe corresponding front clevis 220 on the opposite side and thecorresponding front longitudinal lug 130 of base rib assembly 100 ispositioned between second mounting arm 230 and third mounting arm 235 ofthe corresponding front clevis 220. Retaining members 70, such as bolts,pins, etc., are inserted through mounting holes 132 in each frontlongitudinal lug 130, mounting holes 202 in third side plate 195 andfourth side plate, and mounting holes 242 in each mounting arm 225, 230,235 of each corresponding front clevis 220 to secure vertical stabilizer35 to aircraft fuselage 15.

Similarly, longitudinal lug 210 of fifth side plate 205 is positionedbetween first mounting arm 250 and second mounting arm 255 of thecorresponding rear clevis 245 and the corresponding rear longitudinallug 140 of base rib assembly 100 is positioned between second mountingarm 255 and third mounting arm 260 of the corresponding rear clevis 245.The longitudinal lug of the sixth side plate is similarly positionedbetween first mounting arm 250 and second mounting arm 255 of thecorresponding rear clevis 245 on the opposite side and the correspondingrear longitudinal lug 140 of base rib assembly 100 is positioned betweensecond mounting arm 255 and third mounting arm 260 of the correspondingrear clevis 245. Retaining members 70 such as bolts, pins, etc., areinserted through mounting holes 142 in each rear longitudinal lug 140,mounting holes 212 in fifth side plate 205 and sixth side plate, andmounting holes 267 in each mounting arm 250, 255, 260 of eachcorresponding rear clevis 245 to secure vertical stabilizer 35 toaircraft fuselage 15.

To provide lateral support for vertical stabilizer 35, first and secondfront links 285A, B interconnect each of the pair of front lateral lugs135 of front terminal fitting 110 and a corresponding lateral wall 240of one of the pair of front clevises 220 via retaining members 75, suchas bolts, pins, etc., that extend through mounting holes 137 in frontlateral lugs 135 and mounting holes 244 in lateral walls 240 of frontclevises 220. Similarly, first and second rear links 290A, Binterconnect each of the pair of rear lateral lugs 145 of rear terminalfitting 115 and a corresponding lateral wall 265 of one of the pair ofrear clevises 245 via retaining members 75, such as bolts, pins, etc.,that extend through mounting holes 147 in rear lateral lugs 145 andmounting holes 269 in lateral walls 265 of rear clevises 245.

To attach vertical stabilizer 35 to aircraft fuselage 15 as discussedabove, base rib assembly 100 is first assembled, which, as discussedabove, has a pair of opposing front longitudinal lugs 130, a pair ofopposing rear longitudinal lugs 140, at least one pair of opposingmiddle longitudinal lugs 150, 155 between front longitudinal lugs 130and rear longitudinal lugs 140, and pairs of front and rear lateral lugs135, 145, each of which have a corresponding mounting hole 132, 142,152, 157, 137, 147. To assemble base rib assembly 100, first side chord120 is attached to base rib 105, second side chord 125 is attached tobase rib 105, opposite first side chord 120, front terminal fitting 110is attached to base rib 105, and rear terminal fitting 115 is attachedto base rib 105, opposite front terminal fitting 110. Base rib assembly100 is then inserted into interior 65 of multi-spar box 40 of verticalstabilizer 35 and L-shaped shear clips 160 are attached between midspars 55 and base rib assembly 100.

Front plate 165 is then positioned adjacent exterior surface 47, oradjacent an interior surface, of front spar 45 and is secured to frontspar 45 and base rib assembly 100, rear plate 175 is positioned adjacentexterior surface 52, or adjacent an interior surface, of rear spar 50,opposite front plate 165, and is secured to rear spar 50 and base ribassembly 100, first side plate 185 is positioned adjacent exteriorsurface 62A of first side skin 60A of multi-spar box 40 and is securedto first side skin 60A and base rib assembly 100, and the second sideplate is positioned adjacent exterior surface 62B of second side skin60B of multi-spar box 40 and is secured to second side skin 60B and baserib assembly 100.

Front clevises 220, rear clevises 245, and middle clevises 270 areinserted through corresponding apertures 30 in outer skin 25 of aircraftfuselage 15 and are secured to corresponding frame members 20 ofaircraft fuselage, for example, with bolts, screws, rivets, welding,etc. Front clevises 220 correspond to front longitudinal lugs 130 andeach have first, second, and third mounting arms 225, 230, 235 withmounting holes 242 and rear clevises 245 correspond to rear longitudinallugs 140 and each have first, second, and third mounting arms 250, 255,260 with mounting holes 267. Middle clevises 270 correspond to middlelongitudinal lugs 150, 155 and each have only first and second mountingarms 275, 280 with mounting holes 282.

Vertical stabilizer 35 is then positioned adjacent aircraft fuselage 15such that each front, rear, and middle longitudinal lug 130, 140, 150,155 is aligned with a corresponding front, rear, or middle clevis 220,245, 270 and retaining members 70 are inserted through mounting holes132, 142, 152, 157 of each longitudinal lug 130, 140, 150, 155 andmounting holes 242, 267, 282 of each corresponding clevis 220, 245, 270to secure vertical stabilizer 35 to aircraft fuselage 15. Each frontlateral lug 135 is attached to a first end of a corresponding front link285A, 285B with retaining members 75 and a second end of front links285A, 285B is attached to corresponding lateral clevises, which in theexample shown are lateral walls 240 of front clevises 220. Similarly,each rear lateral lug 145 is attached to a first end of a correspondingrear link 290A, 290B with retaining members 75 and a second end of rearlinks 490A, 490B is attached to corresponding lateral devises, which inthe example shown are lateral walls 265 of rear clevises 245.

Referring to FIGS. 11-17, a second example connection between aircraftfuselage 15 and multi-spar box 40 of vertical stabilizer 35 is shown. Asbest seen in FIGS. 11-12, a base rib assembly 300 has a base rib 305 anda front terminal fitting 310, rear terminal fitting 315 opposite frontterminal fitting 310, first side chord 320, and second side chord 325opposite first side chord 320, attached to base rib 305. Front terminalfitting 310 includes a pair of opposing front longitudinal lugs 330extending parallel to a longitudinal axis A of base rib assembly 300 anda pair of front lateral lugs 335 extending perpendicular to longitudinalaxis A and positioned between the pair of front longitudinal lugs 330.As shown, front terminal fitting 310 is a single, unitary piece havingboth front longitudinal lugs 330 and front lateral lugs 335, but couldalso be two pieces, each having one front longitudinal lug 330 and onefront lateral lug 335, as shown in FIGS. 4-5. Rear terminal fitting 315includes a pair of opposing rear longitudinal lugs 340 extendingparallel to longitudinal axis A and a pair of rear lateral lugs 345extending perpendicular to longitudinal axis A and positioned betweenthe pair of rear longitudinal lugs 340. As shown, rear terminal fitting315 is a single unitary piece having both rear longitudinal lugs 340 andboth rear lateral lugs 345, but could also be two pieces, each havingone rear longitudinal lug 340 and one rear lateral lug 345. First sidechord 320 has at least one first middle longitudinal lug 350 extendingparallel to longitudinal axis A and second side chord 325 has at leastone second middle longitudinal lug 355, opposite first longitudinal lug350. As shown, first side chord 320 has two first longitudinal lugs 350and second side chord 325 has two second longitudinal lugs 355, however,first and second side chords 320, 325 can have any number oflongitudinal lugs desired for a particular application. In addition, inthe particular example shown, there are no lateral lugs positionedbetween first longitudinal lugs 350 and second longitudinal lugs 355.Therefore, in the example shown in FIGS. 11-17, base rib assembly 300has a pair of opposing front longitudinal lugs 330, a pair of opposingrear longitudinal lugs 340, at least one pair of opposing middlelongitudinal lugs 350, 355 disposed between front longitudinal lugs 330and rear longitudinal lugs 340, a pair of front lateral lugs 335disposed between front longitudinal lugs 330, and a pair of rear laterallugs 345 disposed between rear longitudinal lugs 340.

As seen in FIGS. 13-14, base rib assembly 300 is positioned in interior65 of multi-spar box 40 and secured to multi-spar box 40. For example,front terminal fitting 310 of base rib assembly 300 can be secured tofront spar 45 of multi-spar box 40 with screws, bolts, welding, or anyother well-known securement method. Similarly, rear terminal fitting 315can be secured to rear spar 50 with screws, bolts, welding, or any otherwell-known securement method. In addition, mid spars 55 can be securedto base rib assembly 300 by attaching L-shaped shear clips 360 betweenbase rib 305 and/or first and second side chords 320,325 of base ribassembly 300 and mid spars 55 with screws, bolts, welding, or any otherwell-known securement method.

Referring to FIG. 14, with base rib assembly 300 positioned inmulti-spar box 40, a front plate 365 is positioned adjacent exteriorsurface 47, or adjacent an interior surface, of front spar 45 and issecured to front spar 45 and base rib assembly 300, for example, byscrews that are threaded through front plate 365, front spar 45, andfront terminal fitting 310 of base rib assembly 300. Alternatively,front plates 365 can be secured to second front spar 45 and base ribassembly 300 by bolts, welding, or any other well-known securementmethod. Front plate 365 includes lateral lugs 370 that correspond toeach of the front lateral lugs 335 of front terminal fitting 310 andthat are adjacent to and aligned with corresponding front lateral lugs335. As shown, front plate 365 is a single, unitary piece including bothlateral lugs 370, but could also be two or more pieces, each having asingle lateral lug 370 that corresponds to a front lateral lug 335.Similarly, a rear plate 375 is positioned adjacent exterior surface 52,or adjacent an interior surface, of rear spar 50, opposite front plate365, and is secured to rear spar 50 and base rib assembly 300, forexample, by screws that are threaded through rear plate 375, rear spar50, and rear terminal fitting 315 of base rib assembly 300.Alternatively, rear plate 375 can be secured to rear spar 50 and baserib assembly 300 by bolts, welding, or any other well-known securementmethod. Rear plate 375 includes lateral lugs 380 that correspond to eachof the rear lateral lugs 345 of rear terminal fitting 315 and that areadjacent to and aligned with corresponding rear lateral lugs 345. Asshown, rear plate 375 is a single, unitary piece including both laterallugs 380, but could also be two or more pieces, each having a singlelateral lug 380 that corresponds to a rear lateral lug 345.

First side plates 385 are positioned adjacent exterior surface 62A offirst side skin 60A and are secured to first side skin 60A and base ribassembly 300, for example, by screws that are threaded through firstside plates 385, first side skin 60A, and first side chord 320.Alternatively, first side plates 385 can be secured to first side skin60A and base rib assembly 300 by bolts, welding, or any other well-knownsecurement method. Each first side plate 385 includes a longitudinal lug390 that is adjacent to and aligned with a corresponding first middlelongitudinal lug 350. In the example shown, there are two first sideplates 385 since there are two first middle longitudinal lugs 350.However, there could be any number of first side plates 385 as requiredfor the number of first middle longitudinal lugs 350. In addition,rather than individual first side plates 385, a single, unitary piecefirst side plate could be used that has multiple longitudinal lugs thateach correspond to a first middle longitudinal lug. Corresponding secondside plates (not shown) are also positioned adjacent exterior surface62B of second side skin 60B, opposite corresponding first side plates385, and are secured to second side skin 60B and base rib assembly 300,for example, by screws that are threaded through the second side plates,second side skin 60B, and second side chord 325. Alternatively, secondside plates can be secured to second side skin 60B and base rib assembly300 by bolts, welding, or any other well-known securement method. Eachsecond side plate includes a longitudinal lug that is adjacent to andaligned with a corresponding second middle longitudinal lug 355. As withfirst side plates 385, there could be any number of second side platesas required for the number of second middle longitudinal lugs 355 or,rather than individual second side plates, a single, unitary piecesecond side plate could be used that has multiple longitudinal lugs thateach correspond to a second middle longitudinal lug 355.

Third side plate 395 is positioned adjacent exterior surface 62A offirst side skin 60A and is secured to first side skin 60A and base ribassembly 300, for example, by screws that are threaded through thirdside plate 395, first side skin 60A, and front terminal fitting 310.Alternatively, third side plates 395 can be secured to first side skin60A and base rib assembly 300 by bolts, welding, or any other well-knownsecurement method. Third side plate 395 includes a longitudinal lug 400that is adjacent to and aligned with a corresponding front longitudinallug 330. Corresponding fourth side plate (not shown) is also positionedadjacent exterior surface 62B of second side skin 60B, oppositecorresponding third side plate 395, and is secured to second side skin60B and base rib assembly 300, for example, by screws that are threadedthrough the fourth side plate, second side skin 60B, and front terminalfitting 310. Alternatively, sourth side plates can be secured to secondside skin 60B and base rib assembly 300 by bolts, welding, or any otherwell-known securement method. Fourth side plate includes a longitudinallug that is adjacent to and aligned with a corresponding frontlongitudinal lug 330.

Fifth side plate 405 is positioned adjacent exterior surface 62A offirst side skin 60A and is secured to first side skin 60A and base ribassembly 300, for example, by screws that are threaded through fifthside plate 405, first side skin 60A, and rear terminal fitting 315.Alternatively, fifth side plates 405 can be secured to first side skin60A and base rib assembly 300 by bolts, welding, or any other well-knownsecurement method. Fifth side plate 405 includes a longitudinal lug 410that is adjacent to and aligned with a corresponding rear longitudinallug 340. Corresponding sixth side plate (not shown) is also positionedadjacent exterior surface 62B of second side skin 60B, oppositecorresponding fifth side plates 405, and is secured to second side skin60B and base rib assembly 300, for example, by screws that are threadedthrough the sixth side plate, second side skin 60B, and rear terminalfitting 315. Alternatively, sixth side plates can be secured to secondside skin 60B and base rib assembly 300 by bolts, welding, or any otherwell-known securement method. Sixth side plate includes a longitudinallug that is adjacent to and aligned with a corresponding rearlongitudinal lug 340.

Referring to FIG. 15, a pair of front clevises 420 correspond to thepair of front longitudinal lugs 330 and each front clevis 420 extendsthrough a corresponding aperture 30 in outer skin 25 and is secured to aframe member 20 of aircraft fuselage 15. In the example shown, frontclevises 420 each have first and second mounting arms 425, 430.Similarly, a pair of rear clevises 445 correspond to the pair of rearlongitudinal lugs 340 and each rear clevis 445 extends through acorresponding aperture 30 in outer skin 25 and is secured to a framemember 20 of aircraft fuselage 15. In the example shown, rear clevises445 each have first and second mounting arms 450, 455. Pairs of middleclevises 470 correspond to the pairs of middle longitudinal lugs 350,355 and each middle clevis 470 extends through a corresponding aperture30 in outer skin 25 and is secured to a frame member 20 of aircraftfuselage 15. Middle clevises 470 each have first and second mountingarms 475, 480. A front lateral clevis 435 is positioned between the pairof front clevises 420 and extends through a corresponding aperture 30 inouter skin 25 and is secured to a frame member 20 of aircraft fuselage15. A rear lateral clevis 460 is positioned between the pair of rearclevises 445 and extends through a corresponding aperture 30 in outerskin 25 and is secured to a frame member 20 of aircraft fuselage 15.

Referring to FIGS. 16-17, longitudinal lugs 390 of first side plates 385and corresponding first middle longitudinal lugs 350 of base ribassembly 300 are positioned between first mounting arm 475 and secondmounting arm 480 of the corresponding middle clevis 470 and longitudinallugs of second side plates (now shown) and corresponding second middlelongitudinal lugs 355 of base rib assembly 300 are positioned betweenfirst mounting arm 475 and second mounting arm 480 of the correspondingmiddle clevis 470. Retaining members 70, such as bolts, pins, etc., areinserted through mounting holes 352, 357 in each middle longitudinal lug350, 355, mounting holes 392 in first side plate 385 and second sideplate, and mounting holes 482 in each mounting arm 475, 480 of eachcorresponding middle clevis 470 to secure vertical stabilizer 35 toaircraft fuselage 15.

In addition, longitudinal lug 400 of third side plate 395 andcorresponding front longitudinal lug 330 of base rib assembly 300 arepositioned between first mounting arm 425 and second mounting arm 430 ofthe corresponding front clevis 420. The longitudinal lug of the fourthside plate and the corresponding front longitudinal lug 330 of base ribassembly 300 are similarly positioned between first mounting arm 425 andsecond mounting arm 430 of the corresponding front clevis 420. Retainingmembers 70, such as bolts, pins, etc., are inserted through mountingholes 332 in each front longitudinal lug 330, mounting holes 402 inthird side plate 395 and fourth side plate, and mounting holes 442 ineach mounting arm 425, 430 of each corresponding front clevis 420 tosecure vertical stabilizer 35 to aircraft fuselage 15.

Similarly, longitudinal lug 410 of fifth side plate 405 and thecorresponding rear longitudinal lug 340 of base rib assembly 300 arepositioned between first mounting arm 450 and second mounting arm 455 ofthe corresponding rear clevis 445. The longitudinal lug of the sixthside plate and the corresponding rear longitudinal lug 340 of base ribassembly 300 are similarly positioned between first mounting arm 450 andsecond mounting arm 455 of the corresponding rear clevis 445. Retainingmembers 70 such as bolts, pins, etc., are inserted through mountingholes 342 in each rear longitudinal lug 340, mounting holes 412 in fifthside plate 405 and sixth side plate, and mounting holes 467 in eachmounting arm 450, 455 of each corresponding rear clevis 445 to securevertical stabilizer 35 to aircraft fuselage 15.

To provide lateral support for vertical stabilizer 35, first and secondfront links 485A, B interconnect each of the pair of front lateral lugs335 of front terminal fitting 310 and front lateral clevis 435 viaretaining members 75, such as bolts, pins, etc., that extend throughmounting holes 337 in front lateral lugs 335 and mounting holes 440 infront lateral clevis 435. Similarly, first and second rear links 490A, Binterconnect each of the pair of rear lateral lugs 345 of rear terminalfitting 315 and rear lateral clevis 460 via retaining members 75, suchas bolts, pins, etc., that extend through mounting holes 347 in rearlateral lugs 345 and mounting holes 465 in rear lateral clevis 460.

To attach vertical stabilizer 35 to aircraft fuselage 15 as discussedabove, base rib assembly 300 is first assembled, which, as discussedabove, has a pair of opposing front longitudinal lugs 330, a pair ofopposing rear longitudinal lugs 340, at least one pair of opposingmiddle longitudinal lugs 350, 355 between front longitudinal lugs 330and rear longitudinal lugs 340, and pairs of front and rear lateral lugs335, 345, each of which have a corresponding mounting hole 332, 342,352, 357, 337, 347. To assemble base rib assembly 300, first side chord320 is attached to base rib 305, second side chord 325 is attached tobase rib 305, opposite first side chord 320, front terminal fitting 310is attached to base rib 305, and rear terminal fitting 315 is attachedto base rib 305, opposite front terminal fitting 310. Base rib assembly300 is then inserted into interior 65 of multi-spar box 40 of verticalstabilizer 35 and L-shaped shear clips 360 are attached between midspars 55 and base rib assembly 300.

Front plate 365 is then positioned adjacent exterior surface 47, oradjacent an interior surface, of front spar 45 and is secured to frontspar 45 and base rib assembly 300, rear plate 375 is positioned adjacentexterior surface 52, or adjacent an interior surface, of rear spar 50,opposite front plate 365, and is secured to rear spar 50 and base ribassembly 300, first side plate 385 is positioned adjacent exteriorsurface 62A of first side skin 60A of multi-spar box 40 and is securedto first side skin 60A and base rib assembly 300, and the second sideplate is positioned adjacent exterior surface 62B of second side skin60B of multi-spar box 40 and is secured to second side skin 60B and baserib assembly 300.

Front clevises 420, rear clevises 445, and middle clevises 470 areinserted through corresponding apertures 30 in outer skin 25 of aircraftfuselage 15 and are secured to corresponding frame members 20 ofaircraft fuselage 15, for example, with bolts, screws, rivets, welding,etc. Front clevises 420 correspond to front longitudinal lugs 330 andeach have first and second mounting arms 425, 430 with mounting holes442 and rear clevises 445 correspond to rear longitudinal lugs 340 andeach have first and second mounting arms 450, 455 with mounting holes467. Middle clevises 470 correspond to middle longitudinal lugs 350, 355and each have first and second mounting arms 475, 480 with mountingholes 482.

Vertical stabilizer 35 is then positioned adjacent aircraft fuselage 15such that each front, rear, and middle longitudinal lug 330, 340, 350,355 is aligned with a corresponding front, rear, or middle clevis 420,445, 470 and retaining members 70 are inserted through mounting holes332, 342, 352, 357 of each longitudinal lug 330, 340, 350, 355 andmounting holes 442, 467, 482 of each corresponding clevis 420, 445, 470to secure vertical stabilizer 35 to aircraft fuselage 15. Each frontlateral lug 335 is attached to a first end of a corresponding front link485A, 485B with retaining members 75 and a second end of front links485A, 485B is attached to front lateral clevis 435 with retainingmembers 75. Similarly, each rear lateral lug 345 is attached to a firstend of a corresponding rear link 490A, 490B with retaining members 75and a second end of rear links 490A, 490B is attached to rear lateralclevis 460 with retaining members 75.

Referring to FIGS. 18-24, a third example connection between aircraftfuselage 15 and multi-spar box 40 of vertical stabilizer 35 is shown. Asbest seen in FIGS. 18-19, a base rib assembly 500 has a base rib 505 anda front terminal fitting 510, rear terminal fitting 515 opposite frontterminal fitting 510, first side chord 520, and second side chord 525opposite first side chord 520, attached to base rib 505. Front terminalfitting 510 includes a pair of front lateral lugs 535 extendingperpendicular to longitudinal axis A. As shown, front terminal fitting110 is two pieces, each having one front lateral lug 535, but could alsobe a single, unitary piece having both front lateral lugs 535, as shownand described in previous examples. Rear terminal fitting 515 includes apair of rear lateral lugs 545 extending perpendicular to longitudinalaxis A. As shown, rear terminal fitting 515 is two pieces, each havingone rear lateral lug 545, but could also be a single unitary piecehaving both rear lateral lugs 545, as shown and described in previousexamples. First side chord 520 has at least one first middlelongitudinal lug 550 extending parallel to longitudinal axis A andsecond side chord 525 has at least one second middle longitudinal lug555, opposite first longitudinal lug 550. As shown, first side chord 520has two first longitudinal lugs 550 and second side chord 525 has twosecond longitudinal lugs 555, however, first and second side chords 520,525 can have any number of longitudinal lugs desired for a particularapplication. In addition, in the particular example shown, there are nolateral lugs positioned between first longitudinal lugs 550 and secondlongitudinal lugs 555. Therefore, in the example shown in FIGS. 18-19,base rib assembly 500 has at least one pair of opposing middlelongitudinal lugs 550, 555 disposed between a front 500A of base ribassembly 500 and a rear 500B of base rib assembly 500, a pair of frontlateral lugs 535 positioned along front 500A of base rib assembly 500,and a pair of rear lateral lugs 545 positioned along rear 500B of baserib assembly 500.

As seen in FIGS. 20-21, base rib assembly 500 is positioned in interior65 of multi-spar box 40 with first side chord 520 positioned insidefirst side skin 60A, second side chord 525 positioned inside second sideskin 60B, front terminal fitting 510 positioned adjacent exteriorsurface 47, or an interior surface, of front spar 45, and rear terminalfitting 515 positioned adjacent an interior surface, or exterior surface52, of rear spar 50 and base rib assembly 500 secured to multi-spar box40. For example, front terminal fitting 510 of base rib assembly 500 canbe secured to front spar 45 of multi-spar box 40 with screws, bolts,welding, or any other well-known securement method. Similarly, rearterminal fitting 515 can be secured to rear spar 50 with screws, bolts,welding, or any other well-known securement method. In addition, midspars 55 can be secured to base rib assembly 500 by attaching L-shapedshear clips 560 between base rib 505 and/or first and second side chords520, 525 of base rib assembly 500 and mid spars 55 with screws, bolts,welding, or any other well-known securement method.

Referring to FIG. 21, with base rib assembly 500 positioned inmulti-spar box 40 as described above, first side plates 585 arepositioned adjacent exterior surface 62A of first side skin 60A and aresecured to first side skin 60A and base rib assembly 500, for example,by screws that are threaded through first side plates 585, first sideskin 60A, and first side chord 520. Alternatively, first side plates 585can be secured to first side skin 60A and base rib assembly 500 bybolts, welding, or any other well-known securement method. Each firstside plate 585 includes a longitudinal lug 590 that is adjacent to andaligned with a corresponding first middle longitudinal lug 550. In theexample shown, there are two first side plates 585 since there are twofirst middle longitudinal lugs 550. However, there could be any numberof first side plates 585 as required for the number of first middlelongitudinal lugs 550. In addition, rather than individual first sideplates 585, a single, unitary piece first side plate could be used thathas multiple longitudinal lugs that each correspond to a first middlelongitudinal lug. Corresponding second side plates (not shown) are alsopositioned adjacent exterior surface 62B of second side skin 60B,opposite corresponding first side plates 585, and are secured to secondside skin 60B and base rib assembly 500, for example, by screws that arethreaded through the second side plates, second side skin 60B, andsecond side chord 525. Alternatively, second side plates can be securedto second side skin 60B and base rib assembly 500 by bolts, welding, orany other well-known securement method. Each second side plate includesa longitudinal lug that is adjacent to and aligned with a correspondingsecond middle longitudinal lug 555. As with first side plates 585, therecould be any number of second side plates as required for the number ofsecond middle longitudinal lugs 555 or, rather than individual secondside plates, a single, unitary piece second side plate could be usedthat has multiple longitudinal lugs that each correspond to a secondmiddle longitudinal lug 555.

Referring to FIG. 22, a pair of front clevises 620 correspond to thepair of front lateral lugs 535 and each front clevis 620 extends througha corresponding aperture 30 in outer skin 25 and is secured to a framemember 20 of aircraft fuselage 15. In the example shown, front clevises620 each have first and second mounting arms 625, 630. Similarly, a pairof rear clevises 645 correspond to the pair of rear lateral lugs 545 andeach rear clevis 645 extends through a corresponding aperture 30 inouter skin 25 and is secured to a frame member 20 of aircraft fuselage15. In the example shown, rear clevises 645 each have first and secondmounting arms 655, 655. Pairs of middle clevises 670 correspond to thepairs of middle longitudinal lugs 550, 555 and each middle clevis 670extends through a corresponding aperture 30 in outer skin 25 and issecured to a frame member 20 of aircraft fuselage 15. Middle clevises670 each have first and second mounting arms 675, 680.

Referring to FIGS. 23-24, longitudinal lugs 590 of first side plates 585and corresponding first middle longitudinal lugs 550 of base ribassembly 500 are positioned between first mounting arm 675 and secondmounting arm 680 of the corresponding middle clevis 670 and longitudinallugs of second side plates (now shown) and corresponding second middlelongitudinal lugs 555 of base rib assembly 500 are positioned betweenfirst mounting arm 675 and second mounting arm 680 of the correspondingmiddle clevis 670. Retaining members 70, sch as bolts, pins, etc., areinserted through mounting holes 552, 557 in each middle longitudinal lug550, 555, mounting holes 592 in first side plate 585 and second sideplate, and mounting holes 682 in each mounting arm 675, 680 of eachcorresponding middle clevis 670 to secure vertical stabilizer 35 toaircraft fuselage 15.

In addition, to provide lateral support for vertical stabilizer 35,front lateral lugs 535 of base rib assembly 500 are positioned betweenfirst mounting arm 625 and second mounting arm 630 of the correspondingfront clevis 620. Retaining members 70, such as bolts, pins, etc., areinserted through mounting holes 537 in each front lateral lug 535 andmounting holes 642 in each mounting arm 625, 630 of each correspondingfront clevis 620 to secure vertical stabilizer 35 to aircraft fuselage15.

In addition, rear lateral lugs 545 of base rib assembly 500 arepositioned between first mounting arm 655 and second mounting arm 655 ofthe corresponding rear clevis 645. Retaining members 70 such as bolts,pins, etc., are inserted through mounting holes 547 in each rear laterallug 545 and mounting holes 667 in each mounting arm 655, 655 of eachcorresponding rear clevis 645 to secure vertical stabilizer 35 toaircraft fuselage 15.

To attach vertical stabilizer 35 to aircraft fuselage 15 as discussedabove, base rib assembly 500 is first assembled, which, as discussedabove, has at least one pair of opposing middle longitudinal lugs 550,555 disposed between front 500A and rear 500B of base rib assembly 500,and pairs of front and rear lateral lugs 535, 545 disposed along front500A and rear 500B of base rib assembly 500, respectively, each of whichhave a corresponding mounting hole 552, 557, 537, 547. To assemble baserib assembly 500, first side chord 520 is attached to base rib 505,second side chord 525 is attached to base rib 505, opposite first sidechord 520, front terminal fitting 510 is attached to base rib 505, andrear terminal fitting 515 is attached to base rib 505, opposite frontterminal fitting 510. Base rib assembly 500 is then inserted intointerior 65 of multi-spar box 40 of vertical stabilizer 35 and L-shapedshear clips 560 are attached between mid spars 55 and base rib assembly500.

First side plate 585 is then positioned adjacent exterior surface 62A offirst side skin 60A of multi-spar box 40 and is secured to first sideskin 60A and base rib assembly 500, and the second side plate ispositioned adjacent exterior surface 62B of second side skin 60B ofmulti-spar box 40 and is secured to second side skin 60B and base ribassembly 500.

Front clevises 620, rear clevises 645, and middle clevises 670 areinserted through corresponding apertures 30 in outer skin 25 of aircraftfuselage 15 and are secured to corresponding frame members 20 ofaircraft fuselage 15, for example, with bolts, screws, rivets, welding,etc. Front clevises 620 correspond to front lateral lugs 535 and eachhave first and second mounting arms 625, 630 with mounting holes 642 andrear clevises 645 correspond to rear lateral lugs 545 and each havefirst and second mounting arms 655, 655 with mounting holes 667. Middleclevises 670 correspond to middle longitudinal lugs 550, 555 and eachhave first and second mounting arms 675, 680 with mounting holes 682.

Vertical stabilizer 35 is then positioned adjacent aircraft fuselage 15such that each front and rear lateral lug 535, 545 and middlelongitudinal lug 550, 555 is aligned with a corresponding front, rear,or middle clevis 620, 645, 670 and retaining members 70 are insertedthrough mounting holes 537, 547, 552, 557 of each lug 535, 545, 550, 555and mounting holes 642, 667, 682 of each corresponding clevis 620, 645,670 to secure vertical stabilizer 35 to aircraft fuselage 15.

While various embodiments have been described above, this disclosure isnot intended to be limited thereto. Variations can be made to thedisclosed embodiments that are still within the scope of the appendedclaims.

What is claimed:
 1. An aircraft, comprising: an aircraft fuselage havinga plurality of frame members and an outer skin; a vertical stabilizerhaving a multi-spar box, the multi-spar box including a front spar, arear spar, at least one mid spar positioned between and spaced apartfrom the front and rear spars, a first side skin extending between thefront and rear spar, and a second side skin, opposite the first sideskin, extending between the front and rear spar, the front and rearspars and the first and second side skins defining an interior of themulti-spar box; a base rib assembly positioned in the interior of themulti-spar box and secured to the multi-spar box, the base rib assemblyhaving a pair of opposing front longitudinal lugs, a pair of opposingrear longitudinal lugs, and at least one pair of opposing middlelongitudinal lugs disposed between the front longitudinal lugs and therear longitudinal lugs; a pair of front clevises corresponding to thepair of front longitudinal lugs, the front clevises extending throughcorresponding apertures in the outer skin and secured to one of theplurality of frame members, each front clevis having a first mountingarm, a second mounting arm, and a third mounting arm; a pair of rearclevises corresponding to the pair of rear longitudinal lugs, the rearclevises extending through corresponding apertures in the outer skin andsecured to one of the plurality of frame members, each rear clevishaving a first mounting arm, a second mounting arm, and a third mountingarm; a pair of middle clevises corresponding to the pair of middlelongitudinal lugs, the middle clevises extending through correspondingapertures in the outer skin and secured to one of the plurality of framemembers, each middle clevis having only a first mounting arm and asecond mounting arm; and a plurality of retaining members insertedthrough mounting holes in each front, middle, and rear longitudinal lugsand through mounting holes in each corresponding front, middle, and rearclevises to secure the vertical stabilizer to the aircraft fuselage. 2.The aircraft of claim 1, wherein the base rib assembly comprises atleast one front lateral lug positioned between the pair of frontlongitudinal lugs and at least one rear lateral lug positioned betweenthe pair of rear longitudinal lugs.
 3. The aircraft of claim 2, whereinthe base rib assembly does not have any lateral lugs between the atleast one pair of middle lugs.
 4. The aircraft of claim 2, comprising: afront lateral clevis positioned between the pair of front clevises, thefront lateral clevis extending through an aperture in the outer skin andsecured to one of the plurality of frame members; a rear lateral clevispositioned between the pair of rear clevises, the rear lateral clevisextending through an aperture in the outer skin and secured to one ofthe plurality of frame members; a front link interconnecting the frontlateral clevis and the at least one front lateral lug; and a rear linkinterconnecting the rear lateral clevis and the at least one rearlateral lug.
 5. The aircraft of claim 4, comprising: a second front linkinterconnecting the front lateral clevis and another front lateral lug;and a second rear link interconnecting the rear lateral clevis andanother rear lateral lug.
 6. The aircraft of claim 2, comprising: afront link interconnecting the at least one front lateral lug and alateral wall of one of the pair of front clevises; and a rear linkinterconnecting the at least one rear lateral lug and a lateral wall ofone of the pair of rear clevises.
 7. The aircraft of claim 6,comprising: a second front link interconnecting another front laterallug and a lateral wall of the other one of the pair of front clevises;and a second rear link interconnecting another rear lateral lug and alateral wall of the other one of the pair of rear clevises.
 8. Theaircraft of claim 2, comprising: a front plate adjacent an exteriorsurface of the front spar and secured to the front spar and the base ribassembly, the front plate having a lateral lug adjacent to and alignedwith the at least one front lateral lug of the base rib assembly; a rearplate adjacent an exterior surface of the rear spar, opposite the frontplate, and secured to the rear spar and the base rib assembly, the rearplate having at least one lateral lug adjacent to and aligned with theat least one rear lateral lug of the base rib assembly; a first sideplate adjacent an exterior surface of the first side skin and secured tothe first side skin and the base rib assembly, the first side platehaving at least one longitudinal lug adjacent to and aligned with one ofthe middle longitudinal lugs of the base rib assembly; and a second sideplate adjacent an exterior surface of the second side skin and securedto the second side skin and the base rib assembly, the second side platehaving at least one longitudinal lug adjacent to and aligned withanother of the middle longitudinal lugs of the base rib assembly.
 9. Theaircraft of claim 8, wherein: the at least one longitudinal lug of thefirst side plate and the corresponding middle longitudinal lug of thebase rib assembly are positioned between the first mounting arm and thesecond mounting arm of the corresponding middle clevis; and the at leastone longitudinal lug of the second side plate and the correspondingmiddle longitudinal lug of the base rib assembly are positioned betweenthe first mounting arm and the second mounting arm of the correspondingmiddle clevis.
 10. The aircraft of claim 9, comprising: a third sideplate adjacent an exterior surface of the first side skin and secured tothe first side skin and the base rib assembly, the third side platehaving at least one longitudinal lug aligned with one of the frontlongitudinal lugs of the base rib assembly; and a fourth side plateadjacent an exterior surface of the second side skin and secured to thesecond side skin and the base rib assembly, the fourth side plate havingat least one longitudinal lug aligned with another of the frontlongitudinal lugs of the base rib assembly.
 11. The aircraft of claim10, wherein: the at least one longitudinal lug of the third side plateis positioned between the first mounting arm and the second mounting armof a first front clevis of the pair of front clevises and acorresponding front longitudinal lug of the base rib assembly ispositioned between the second mounting arm and the third mounting arm ofthe first front clevis; and the at least one longitudinal lug of thefourth side plate is positioned between the first mounting arm and thesecond mounting arm of a second front clevis of the pair of frontclevises and a corresponding front longitudinal lug of the base ribassembly is positioned between the second mounting arm and the thirdmounting arm of the second front clevis.
 12. The aircraft of claim 10,comprising: a fifth side plate adjacent an exterior surface of the firstside skin and secured to the first side skin and the base rib assembly,the fifth side plate having at least one longitudinal lug aligned withone of the rear longitudinal lugs of the base rib assembly; and a sixthside plate adjacent an exterior surface of the second side skin andsecured to the second side skin and the base rib assembly, the sixthside plate having at least one longitudinal lug aligned with another ofthe rear longitudinal lugs of the base rib assembly.
 13. The aircraft ofclaim 12, wherein: the at least one longitudinal lug of the fifth sideplate is positioned between the first mounting arm and the secondmounting arm of a first rear clevis of the pair of rear clevises and acorresponding rear longitudinal lug of the base rib assembly ispositioned between the second mounting arm and the third mounting arm ofthe first rear clevis; and the at least one longitudinal lug of thesixth side plate is positioned between the first mounting arm and thesecond mounting arm of a second rear clevis of the pair of rear clevisesand a corresponding rear longitudinal lug of the base rib assembly ispositioned between the second mounting arm and the third mounting arm ofthe second rear clevis.
 14. A method of attaching a vertical stabilizerhaving a multi-spar box to an aircraft fuselage, the method comprisingthe steps of: assembling a base rib assembly having a pair of opposingfront longitudinal lugs, a pair of opposing rear longitudinal lugs, atleast one pair of opposing middle longitudinal lugs disposed between thefront longitudinal lugs and the rear longitudinal lugs, and a pluralityof lateral lugs, each longitudinal lug and each lateral lug having acorresponding mounting hole; inserting the base rib assembly into aninterior of the multi-spar box of the vertical stabilizer, the interiorof the multi-spar box defined by a front spar, a rear spar, and opposingside skins; positioning a front plate adjacent an exterior surface ofthe front spar and securing the front plate to the front spar and thebase rib assembly, the front plate having at least one lateral lugcorresponding to one of the plurality of lateral lugs of the base ribassembly, the at least one lateral lug of the front plate having amounting hole that aligns with the mounting hole in the correspondinglateral lug of the base rib assembly; positioning a rear plate adjacentan exterior surface of the rear spar, opposite the front plate, andsecuring the rear plate to the rear spar and the base rib assembly, therear plate having at least one lateral lug corresponding to one of theplurality of lateral lugs of the base rib assembly, the at least onelateral lug of the rear plate having a mounting hole that aligns withthe mounting hole in the corresponding lateral lug of the base ribassembly; positioning a first side plate adjacent an exterior surface ofa first side skin of the multi-spar box and securing the first sideplate to the first side skin and the base rib assembly, the first sideplate having at least one longitudinal lug corresponding to one of thelongitudinal lugs of the base rib assembly, each of the at least onelongitudinal lug of the first side plate having a mounting hole thataligns with the mounting hole in the corresponding longitudinal lug ofthe base rib assembly; positioning a second side plate adjacent anexterior surface of a second side skin of the multi-spar box andsecuring the second side plate to the second side skin and the base ribassembly, the second side plate having at least one longitudinal lugcorresponding to one of the longitudinal lugs of the base rib assembly,each of the at least one longitudinal lug of the second side platehaving a mounting hole that aligns with the mounting hole in thecorresponding longitudinal lug of the base rib assembly; inserting aplurality of clevises through corresponding apertures in a skin of theaircraft fuselage and securing each of the plurality of clevises to aframe member of the aircraft fuselage, wherein the clevisescorresponding to the front longitudinal lugs and the rear longitudinallugs each have a first, second, and third mounting arms, each mountingarm having a mounting hole, and the clevises corresponding to the middlelongitudinal lugs each have first and second mounting arms, eachmounting arm having a mounting hole; positioning the vertical stabilizeradjacent the aircraft fuselage and aligning each longitudinal lug with acorresponding clevis; and inserting a retaining member through themounting hole of each corresponding longitudinal lug and clevis tosecure the vertical stabilizer to the aircraft fuselage.
 15. The methodof claim 14, attaching each lateral lug to a first end of acorresponding lateral link and attaching a second end of each laterallink to a lateral clevis.
 16. The method of claim 15, wherein eachlateral clevis is part of a corresponding clevis.
 17. The method ofclaim 15, wherein each lateral clevis is positioned between twoclevises, extends through a corresponding aperture in the skin of theaircraft fuselage, and is secured to a frame member of the aircraftfuselage.
 18. The method of claim 14, wherein assembling the base ribassembly comprises: attaching at least one first side chord to a baserib, the at least one first side chord including at least one of theplurality of longitudinal lugs; attaching at least one second side chordto the base rib, opposite the at least one first side chord, the atleast one second side chord including at least one of the plurality oflongitudinal lugs; attaching a front terminal fitting to the base rib,the front terminal fitting including at least one of the plurality oflongitudinal lugs and at least one of the plurality of lateral lugs; andattaching a rear terminal fitting to the base rib, opposite the frontterminal fitting, the rear terminal fitting including at least one ofthe plurality of longitudinal lugs and at least one of the plurality oflateral lugs.
 19. The method of claim 14, further comprising attachingat least one generally L-shaped shear clip between the base rib assemblyand a mid spar of the multi-spar box.
 20. The method of claim 14,wherein the plurality of lateral lugs are located at a front of the baserib assembly and a rear of the base rib assembly and no lateral lugs arelocated between the front and the rear of the base rib assembly.